The emergence of the mouse as the preeminent research tool for the investigation of normal human biology and disease has lead to a dramatic increase in the production of genetically engineered mice. The NIH meeting on "Priority Setting for Mouse Genomics and Genetics Resources" endorsed the concept of a Mutant Mouse Regional Resource Centers (MMRRC) program to ensure the continued availability of these valuable mice to the research community. The MMRRCs comprise a network of interactive research resource centers that will import, cryopreserve, and distribute selected induced mutant strains of mice. Crucial to the success of this program is the insurance of high standards for monitoring animal health and genetic integrity. Equally important is the establishment of an efficient informatics network to coordinate the activities of the MMRRCs. An Informatics Coordinating Center (ICC) will develop databases to maintain data on inventories at each site, coordinate orders, provide genetic and phenotypic information about strains held at each site, and maintain a public web site that will provide access to subsets of these data and advertise the availability of strains. The NIH priority setting group suggested that the MMRRCs should collaborate with The Jackson Laboratory to avoid duplication of effort. The Jackson Laboratory has extensive experience in the preservation, propagation, and distribution of mutant strains of mice, and in the development of informatics resources needed to support these efforts. We propose to establish the ICC at The Jackson Laboratory and to develop and maintain the informatics network for the MMRRC program. We propose to 1) develop and maintain an inventory database containing updated data on all strains maintained in the MMRRCs and The Jackson Laboratory's Induced Mutant Resource, with appropriate links to other databases; 2) develop and implement an information network linking the MMRRCs and the ICC; 3) develop and maintain an ICC Web page to provide access to strain data, on-line ordering and information request forms, and appropriate links; and 4) establish and implement procedures for coordinating investigator support services and distribution.